#!/bin/sh
# Detect AC power or not in a portable way
# Copyright (c) 2007-2009 Roy Marples <roy@marples.name>

# Exit 0 if on AC power, 1 if not and 255 if we don't know how to work it out
if [ -f /proc/acpi/ac_adapter/*/state ]; then
	cat /proc/acpi/ac_adapter/*/state | while read line; do
		case "$line" in
		"state:"*"off-line") exit 128;;
		esac
	done
elif [ -f /sys/class/power_supply/*/online ]; then
	cat /sys/class/power_supply/*/online | while read line; do
		[ "${line}" = 0 ] && exit 128
	done
elif [ -f /proc/pmu/info ]; then
	cat /proc/pmu/info | while read line; do
		case "$line" in
		"AC Power"*": 0") exit 128;;
		esac
	done
elif command -v envstat >/dev/null 2>&1; then
	# NetBSD has envstat
	envstat -d acpiacad0 2>/dev/null | while read line; do
		case "$line" in
		"connected:"*"OFF") exit 128;;
		esac
	done
elif sysctl -q hw.acpi.acline >/dev/null 2>/dev/null; then
	case $(sysctl -n hw.acpi.acline) in
	0) exit 1;;
	*) exit 0;;
	esac
else
	exit 255
fi
[ $? != 128 ]
